Aromatic polyimides and copolyimides containing bulky t-butyltriphenylmethane units

Castro-Blanco, Rafael A.; Rojas-Rodríguez, Mario; Hernández, Antonio; Lozano, Ángel E.; Alexandrova, Larissa; Aguilar‐Lugo, Carla

doi:10.1007/s00289-019-03003-7

Cited by 6 publications

(3 citation statements)

References 60 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this article we report the synthesis in a single step of N ‐phenyl substituted polybenzimidazoles starting from N ‐substituted tetraamine, 4,6‐di( N ‐phenylamine)‐1,3‐diaminebenzene (Ph‐BET), under mild reaction conditions. The phenyl substituent was chosen principally due to three reasons: (1) it is bulky enough to give an important increase in the polymer free volume; (2) it should be less affected by the harsh conditions of the polycondensation and the resulting polymers will have high aromatic content to maintain good thermal properties; and (3) synthesis of this tetraamine is relatively simple and effective …”

Section: Introductionmentioning

confidence: 99%

Processable N‐Substituted Polybenzimidazole; Direct Synthesis

et al. 2020

Self Cite

View full text Add to dashboard Cite

In this work, the preparations of N‐phenyl substituted polybenzimidazoles by direct polycondensation between N‐phenyl substituted aromatic tetramine, 4,6‐di(N‐phenylamine)‐1,3‐diaminebenzene, and dicarboxylic acids in Eaton's reagent are reported. It is shown that the factors of concentration and temperature are very important for synthesis of soluble linear polymer structures. The high temperatures promote strong crosslinking reactions resulting in insoluble gel fraction. Only decreasing the reaction temperature to 90 °C it is possible to obtained soluble polymer of high molecular weights with inherent viscosity of 1.6 dL/g. Although the FTIR and 1H NMR analyses demonstrated incomplete cyclization of thus obtained polymers, but they are readily soluble in organic solvents and the good quality films were prepared by solution casting. In order to complete the cyclization films were undergone by thermal treatment at 320 °C during 1 h. The N‐phenyl substituted polybenzimidazoles demonstrated good thermal and mechanical properties, which were compared to their analog unsubstituted polybenzimidazoles obtained from 1,2,4,5‐Benzenetetramine tetra‐hydrochloride using similar synthetic conditions.

show abstract

Section: Introductionmentioning

confidence: 99%

Processable N‐Substituted Polybenzimidazole; Direct Synthesis

et al. 2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…And the chemical structure modification of PI is usually achieved by changing the structure of dianhydride or diamine to adjust the FFV and gas transport performance 20 . Numerous studies have reported that the introduction of bulky side groups, 21, 22 flexible units, 23 non‐coplanar and asymmetric structures, 24–27 etc., into the polymer backbone is an effective method to decrease the regularity of polymer chains and weaken the accumulation of molecular chains, which greatly improve gas permeability of the polymer while maintaining moderate selectivity. In addition, the presence of fluorine in polymer chains improves the solubility, hydrophobicity, optical transparency and FFV, which is attributed to the unique physical and chemical properties of the fluorine atom, including low molar polarizability, small atomic radius and large electronegativity 28–31 .…”

Section: Introductionmentioning

confidence: 99%

Design, synthesis and characterization of novel fluorinated polyimide membranes with bulky pendant for gas transport

Lai

Niu

et al. 2023

Polymer International

View full text Add to dashboard Cite

Three novel fluorinated polyimides (PIs) were synthesized via one‐step solution polycondensation from a new diamine monomer, 4‐(3‐methoxy‐4‐(difluoromethoxy)phenyl)‐2,6‐bis(4‐aminophenyl)pyridine, and three commercially available aromatic dianhydrides. The solubility, thermal, optical, hydrophobic and gas transport properties of the obtained PIs were investigated. The results demonstrated that these polymers present good solubility in dimethylformamide, N‐methylpyrrolidone, dimethylsulfoxide, dimethylacrylamide, CHCl3, tetrahydrofuran and CH2Cl2 at room temperature or upon heating. Meanwhile, they displayed excellent thermal properties with glass transition temperature of 261–345 °C, weight loss temperatures at 10% of 518–523 °C as well as char yield of 60–62% at 800 °C in nitrogen atmosphere. Furthermore, the PI membranes have good hydrophobic properties with water contact angle value in the range 90.1–92.0°. Moreover, they show excellent optical properties, with cut‐off wavelength (λcut‐off) values of 368–381 nm and wavelength values at 80% transmittance (λ80%) of 421–462 nm. The pure gas permeabilities of He, CO2, O2 and N2 of the PI membranes were measured by the method of constant volume–variable pressure. The PI containing 4,4′‐(hexafluoroisopropyl)diphthalic anhydride moiety exhibits the largest molecular chain spacing and free volume, giving the best gas transport performance in this work. Molecular simulation results show that the introduction of fluorine‐containing structure and bulky pendant into polymer backbones is beneficial for gas transport. © 2023 Society of Industrial Chemistry.

show abstract

“…Of all the membrane materials, polyimide presents great potential for development and prospect of application. As is known to all, polyimide is a kind of polymer resin material containing imide ring (–CO–N–CO–) in the main chain, with the advantages of high heat resistance, corrosion resistance, excellent dielectric properties, mechanical properties, and gas separation properties 26–28 . Therefore, as a special engineering material, polyimide has been widely used in aviation, aerospace, microelectronics, nano, liquid crystal, gas separation membrane, laser, medical devices and other fields.…”

Section: Introductionmentioning

confidence: 99%

Synthesis of new copolyimides containing pyridine and morpholine groups for gas separation through molecular design and simulation

Niu

Lai³

et al. 2022

J of Applied Polymer Sci

View full text Add to dashboard Cite

Through one-step copolymerization of 4-(4-[1-morpholinyl]phenyl)-2,6-bis (4-aminophenyl)pyridine (MPAP), 9,9-bis(4-aminophenyl)fluorene (BAFL), and (4,4 0 -hexafluoroisopropylidene)diphthalic anhydride (6FDA), a series of polyimides containing morpholine group, pyridine ring, fluorene "cardo" pendant and hexafluoroisopropyl group are obtained. The synthesized polyimides have good thermal stability, high transparency, outstanding hydrophobicity and excellent solubility in not only high-boiling solvents but also low boilingpoint solvents. Furthermore, polyimide films have large molecular chain spacing, which is consistent with the free volume calculated by molecular simulation. Consequently, polyimide membranes display better gas permeability values of CO 2 (up to 24.47 Barrer) and He (up to 45.04 Barrer), and good ideal gas selectivity values of CO 2 /N 2 (up to 15.33 Barrer) and He/N 2 (up to 23.89 Barrer), which also shows potential application of polyimide matrix materials in gas separation.

show abstract

Aromatic polyimides and copolyimides containing bulky t-butyltriphenylmethane units

Cited by 6 publications

References 60 publications

Processable N‐Substituted Polybenzimidazole; Direct Synthesis

Processable N‐Substituted Polybenzimidazole; Direct Synthesis

Design, synthesis and characterization of novel fluorinated polyimide membranes with bulky pendant for gas transport

Synthesis of new copolyimides containing pyridine and morpholine groups for gas separation through molecular design and simulation

Contact Info

Product

Resources

About